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Ddt
Dichlorodiphenyltrichloroethane, commonly known as DDT, is a colorless, tasteless, and almost odorless crystalline chemical compound, an organochloride. Originally developed as an insecticide, it became infamous for its environmental impacts. DDT was first synthesized in 1874 by the Austrian chemist Othmar Zeidler. DDT's insecticidal action was discovered by the Swiss chemist Paul Hermann Müller in 1939. DDT was used in the second half of World War II to limit the spread of the insect-borne diseases malaria and typhus among civilians and troops. Müller was awarded the Nobel Prize in Physiology or Medicine in 1948 "for his discovery of the high efficiency of DDT as a contact poison against several arthropods". By October 1945, DDT was available for public sale in the United States. Although it was promoted by government and industry for use as an agricultural and household pesticide, there were also concerns about its use from the beginning. Opposition to DDT was focused by t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silent Spring
''Silent Spring'' is an environmental science book by Rachel Carson. Published on September 27, 1962, the book documented the environmental harm caused by the indiscriminate use of pesticides. Carson accused the chemical industry of spreading disinformation, and public officials of accepting the industry's marketing claims unquestioningly. In the late 1950s, Carson began to work on environmental conservation, especially environmental problems that she believed were caused by synthetic pesticides. The result of her research was ''Silent Spring'', which brought environmental concerns to the American public. The book was met with fierce opposition by chemical companies, but it swayed public opinion and led to a reversal in U.S. pesticide policy, a nationwide ban on DDT for agricultural uses, and an environmental movement that led to the creation of the U.S. Environmental Protection Agency.Paull, John (2013"The Rachel Carson Letters and the Making of Silent Spring", Sage Open, 3 ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bald Eagle
The bald eagle (''Haliaeetus leucocephalus'') is a bird of prey found in North America. A sea eagle, it has two known subspecies and forms a species pair with the white-tailed eagle (''Haliaeetus albicilla''), which occupies the same niche as the bald eagle in the Palearctic. Its range includes most of Canada and Alaska, all of the contiguous United States, and northern Mexico. It is found near large bodies of open water with an abundant food supply and old-growth trees for nesting. The bald eagle is an opportunistic feeder which subsists mainly on fish, which it swoops down upon and snatches from the water with its talons. It builds the largest nest of any North American bird and the largest tree nests ever recorded for any animal species, up to deep, wide, and in weight. Sexual maturity is attained at the age of four to five years. Bald eagles are not actually bald; the name derives from an older meaning of the word, "white headed". The adult is mainly brown with a w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bald Eagle
The bald eagle (''Haliaeetus leucocephalus'') is a bird of prey found in North America. A sea eagle, it has two known subspecies and forms a species pair with the white-tailed eagle (''Haliaeetus albicilla''), which occupies the same niche as the bald eagle in the Palearctic. Its range includes most of Canada and Alaska, all of the contiguous United States, and northern Mexico. It is found near large bodies of open water with an abundant food supply and old-growth trees for nesting. The bald eagle is an opportunistic feeder which subsists mainly on fish, which it swoops down upon and snatches from the water with its talons. It builds the largest nest of any North American bird and the largest tree nests ever recorded for any animal species, up to deep, wide, and in weight. Sexual maturity is attained at the age of four to five years. Bald eagles are not actually bald; the name derives from an older meaning of the word, "white headed". The adult is mainly brown with a w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paul Hermann Müller
Paul Hermann Müller, also known as Pauly Mueller (12 January 1899 – 13 October 1965), was a Swiss chemist who received the 1948 Nobel prize in Physiology or Medicine for his 1939 discovery of insecticidal qualities and use of DDT in the control of vector diseases such as malaria and yellow fever. Early life and education Müller was born on 12 January 1899 in Olten, Solothurn, to Gottlieb and Fanny (née Leypoldt or Leypold ) Müller. He was the oldest of four children. His father worked for the Swiss Federal Railways and the family first moved to Lenzburg in Aargau and then to Basel. Müller went to the local primary school ( volksschule) and later to the lower and upper "realschule". In that time, he had a small laboratory where he developed photographic plates and built radio equipment. In 1916 he left school due to bad grades and started to work as a laboratory assistant at Dreyfus. The next year he became an assistant chemist in the scientific-industrial laboratory ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rachel Carson
Rachel Louise Carson (May 27, 1907 – April 14, 1964) was an American marine biologist, writer, and conservationist whose influential book '' Silent Spring'' (1962) and other writings are credited with advancing the global environmental movement. Carson began her career as an aquatic biologist in the U.S. Bureau of Fisheries, and became a full-time nature writer in the 1950s. Her widely praised 1951 bestseller ''The Sea Around Us'' won her a U.S. National Book Award, recognition as a gifted writer and financial security. Her next book, ''The Edge of the Sea'', and the reissued version of her first book, ''Under the Sea Wind'', were also bestsellers. This sea trilogy explores the whole of ocean life from the shores to the depths. Late in the 1950s, Carson turned her attention to conservation, especially some problems she believed were caused by synthetic pesticides. The result was the book ''Silent Spring'' (1962), which brought environmental concerns to an unprecedente ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States Fish And Wildlife Service
The United States Fish and Wildlife Service (USFWS or FWS) is an agency within the United States Department of the Interior dedicated to the management of fish, wildlife, and natural habitats. The mission of the agency is "working with others to conserve, protect, and enhance fish, wildlife, plants and their habitats for the continuing benefit of the American people." Among the responsibilities of the USFWS are enforcing federal wildlife laws; protecting endangered species; managing migratory birds; restoring nationally significant fisheries; conserving and restoring wildlife habitats, such as wetlands; helping foreign governments in international conservation efforts; and distributing money to fish and wildlife agencies of U.S. states through the Wildlife Sport Fish and Restoration Program. The vast majority of fish and wildlife habitats are on state or private land not controlled by the United States government. Therefore, the USFWS works closely with private groups su ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peregrine Falcon
The peregrine falcon (''Falco peregrinus''), also known as the peregrine, and historically as the duck hawk in North America, is a cosmopolitan bird of prey (raptor) in the family Falconidae. A large, crow-sized falcon, it has a blue-grey back, barred white underparts, and a black head. The peregrine is renowned for its speed, reaching over during its characteristic hunting stoop (high-speed dive), making it the fastest bird in the world, as well as the fastest member of the animal kingdom. According to a ''National Geographic'' TV program, the highest measured speed of a peregrine falcon is . As is typical for bird-eating raptors, peregrine falcons are sexually dimorphic, with females being considerably larger than males. The peregrine's breeding range includes land regions from the Arctic tundra to the tropics. It can be found nearly everywhere on Earth, except extreme polar regions, very high mountains, and most tropical rainforests; the only major ice-free landmass fr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Contiguous United States
The contiguous United States (officially the conterminous United States) consists of the 48 adjoining U.S. states and the Federal District of the United States of America. The term excludes the only two non-contiguous states, Alaska and Hawaii (also the last ones admitted to the Union), and all other offshore insular areas, such as American Samoa, Guam, the Northern Mariana Islands, Puerto Rico, and the U.S. Virgin Islands. The colloquial term "Lower48" is used also, especially in relation to just Alaska (Hawaii is farther south). The related but distinct term continental United States includes Alaska (which is also on the continent of North America but separated from the 48 states by British Columbia and Yukon of Canada), but excludes the Hawaiian Islands and all U.S. territories in the Caribbean and the Pacific. The greatest distance (on a great-circle route) entirely within the contiguous U.S. is 2,802 miles (4,509 km), between Florida and the State of Washington; ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crystallinity
Crystallinity refers to the degree of structural order in a solid. In a crystal A crystal or crystalline solid is a solid material whose constituents (such as atoms, molecules, or ions) are arranged in a highly ordered microscopic structure, forming a crystal lattice that extends in all directions. In addition, macro ..., the atoms or molecules are arranged in a regular, periodic manner. The degree of crystallinity has a big influence on hardness, density, Transparency and translucency, transparency and diffusion. In an ideal gas, the relative positions of the atoms or molecules are completely random. Amorphous materials, such as liquids and glasses, represent an intermediate case, having order over short distances (a few atomic or molecular spacings) but not over longer distances. Many materials, such as glass-ceramics and some polymers, can be prepared in such a way as to produce a mixture of crystalline and Amorphous solid, amorphous regions. In such cases, crystall ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methoxychlor
Methoxychlor is a synthetic organochloride insecticide, now obsolete. Usage Methoxychlor was used to protect crops, ornamentals, livestock, and pets against fleas, mosquitoes, cockroaches, and other insects. It was intended to be a replacement for DDT, but has since been banned for use as a pesticide based on its acute toxicity, bioaccumulation, and endocrine disruption activity. The amount of methoxychlor in the environment changes seasonally due to its use in farming and foresting. It does not dissolve readily in water, so it is mixed with a petroleum-based fluid and sprayed, or used as a dust. Sprayed methoxychlor settles on the ground or in aquatic ecosystems, where it can be detected in sediments. Its degradation may take many months. Methoxychlor is ingested and absorbed by living organisms, and it accumulates in the food chain. Some metabolites may have unwanted side effects. Banned The use of methoxychlor as a pesticide was banned in the United States in 2003 and in th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Endangered Species Act
The Endangered Species Act of 1973 (ESA or "The Act"; 16 U.S.C. § 1531 et seq.) is the primary law in the United States for protecting imperiled species. Designed to protect critically imperiled species from extinction as a "consequence of economic growth and development untempered by adequate concern and conservation", the ESA was signed into law by President Richard Nixon on December 28, 1973. The Supreme Court of the United States described it as "the most comprehensive legislation for the preservation of endangered species enacted by any nation"."Tennessee Valley Authority v. Hill" 437 U.S. 153 (1978) Retrieved 24 November 2015. The purposes of the ESA are two-fold: to prevent extinction and to recover species to the point where the law's protections are not needed. It therefor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dicofol
Dicofol is an organochlorine pesticide that is chemically related to DDT. Dicofol is a miticide that is very effective against spider mite. One of the intermediates used in its production is DDT. This has caused criticism by many environmentalists; however, the World Health Organization classifies dicofol as a Level II, "moderately hazardous" pesticide. It is known to be harmful to aquatic animals, and can cause eggshell thinning in various species of birds. Difference between dicofol and DDT Dicofol is structurally similar to DDT. It differs from DDT by the replacement of the hydrogen (H) on C-1 by a hydroxyl (OH) functional group. One of the intermediates used in its production is DDT. Chemistry Dicofol is usually synthesized from technical DDT. During the synthesis, DDT is first chlorinated to an intermediate, Cl-DDT, followed by hydrolyzing to dicofol. After the synthesis reaction, DDT and Cl-DDT may remain in the dicofol product as impurities. * Formula: C14H9Cl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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